For lower wattage uses and a nice quiet generator with a Honda name on it, don't dink around. Get the real Mc'Coy, the ridiculously quiet EU line from honda has very clean power and the Honda reputation. You can use these generator for much more than backup emergency power.
A quiet generator is always better than a loud one but there is very little in between. You pay for that quiet. Most of the time it is worth it but sometimes it is not, one of the times it is not worth it for me is when you are talking about high wattage and/or emergency needs.
Again, depending on the use of the power made by the generator it may not matter how clean the power is. If he is running a computer with this power source then I would again recommend the Honda EUi line for clean steady power. A contractor generator like the dewalt won't have a waveform as clean, frequency as steady, or voltage as consistent as the honda inverter series. Running a light bulb,well pump, or fridge is within the tolerances of most any generator out there.